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Climate-induced phenological shifts may have serious consequences for organisms and populations, but it is challenging to link such shifts to demographic change. Here, we present an overview of current methodological approaches for studying the demographic consequences of phenological shifts, based on a literature survey of 62 studies on diverse taxa. The majority of these studies (66%) were condu
We investigated amorphous Si (ASi) in a boreal wetland in northern Sweden. We found enormous stocks of ASi in the upper soil layers (up to 11% of dry weight), in the form of diatom frustules and plant ASi. A consistent exponential decrease in ASi concentrations was observed with increasing depth in the soil profile. An inverse modeling approach shows that vegetation takes up a substantial part of
Background: The forests of north-west Amazonia are characterised by the highest levels of tree diversity in the world, high rainfall and relatively fertile soils. Aims: Here we present a comprehensive description of the carbon cycle of two 1 ha forests plots in Allpahuayo, near Iquitos, Peru, one on an occasionally inundated alisol/gleysol landscape, the other on an arenosol (sandy soil). Methods:
Stratigraphic boundaries are ideally defined by distinct lithological, geochemical, and palaeobiological signatures, to which a chronological framework can be applied. We present a range of observations that illustrate how the Holocene-Anthropocene transition meets these criteria in its expression in sediments from remote arctic and alpine lakes, removed from direct, catchment-scale, anthropogenic
Forecasting how species and ecosystems will respond to climate change has been a major aim of ecology in recent years. Much of this research has focused on phenology - the timing of life-history events. Phenology has well-demonstrated links to climate, from genetic to landscape scales; yet our ability to explain and predict variation in phenology across species, habitats and time remains poor. Her
Abstract Phenology is an important part of life history that is gaining increased attention because of recent climate change. We use game theory to model phenological adaptation in migratory birds that compete for territories at their breeding grounds. We investigate how the evolutionarily stable strategy (ESS) for the timing of arrival is affected by changes in the onset of spring, the timing of
Pathogens that are maintained by wild birds occasionally jump to human hosts, causing considerable loss of life and disruption to global commerce. Preliminary evidence suggests that climate change and human movements and commerce may have played a role in recent range expansions of avian pathogens. Since the magnitude of climate change in the coming decades is predicted to exceed climatic changes
Relationships between genetic (allozyme) variation and landscape age and structure were investigated in 17 calcareous grassland demes of the moss Homalothecium lutescens (Hedw.) H. Rob. on the Baltic island of Oland. Mean within-deme gene diversity (H-S = 0.152) was moderate compared with other bryophyte studies, and the between-deme proportion of the total diversity (G(ST) = 0.100, Jost's D = 0.0
A high-resolution study of benthic foraminiferal assemblages was performed on a ca. eight metre long sediment core from Gullmar Fjord on the west coast of Sweden. The results of Pb-210- and AMS C-14-datings show that the record includes the two warmest climatic episodes of the last 1500 years: the Medieval Warm Period (MWP) and the recent warming of the 20th century. Both periods are known to be a
The Neotropical jumping plant-louse Russelliana solanicola Tuthill is a potato pest and a probable vector of plant pathogens. Populations morphologically similar to those found on potatoes have been collected on plants of at least ten different families, four of which have been confirmed as hosts by the presence of immatures. This suggests that R. solanicola is either a single polyphagous species
The life-history parameters of most living organisms are modified by fluctuations in environmental conditions. The impact of environmental autocorrelation on population persistence is well understood in single species systems. However, in multi-species communities the impact of stochasticity is complicated by the possibility of different species having differing intrinsic responses to the environm
We determined the proportion of butterfly species that occur as metapopulations with grasslands as the only habitat. We counted all butterflies in 19 semi-natural grassland patches in a forest-dominated landscape in southern Sweden over a 5-y period. Seven of the 44 butterfly species observed exhibited a metapopulation structure. The other species either use grassland mainly for adult feeding but
The release of dissolved silicon (DSi) from A and B horizons was investigated with leaching tests on unsaturated columns. As forest A horizons have larger biogenic Si (BSi) pools than arable lands, we compared the Si release from a forest and a cropland from the same geographical region developed on a Luvisol in Belgium and a Cambisol in Sweden. The A horizons released a quickly dissolving Si frac
Predicted climate change implies warmer weather and a higher frequency of extreme weather situations. The consequences of the warm July in 2003 was investigated in contrast to the cold July in 2004 in southern Sweden with focus on the dispersal rate of two species of burnet moths (Zygaenidae). During an extensive mark-release-recapture program in metapopulations of burnet moths substantial differe
We quantified the utilization of terrestrial organic matter (OM) in the food web of a humic lake by analyzing the metabolism and the consumers' stable isotopic (C, H, N) composition in benthic and pelagic habitats. Terrestrial OM inputs (3 g C m(-2) d(-1)) to the lake greatly exceeded autochthonous OM production (3 mg C m(-2) d(-1)) in the lake. Heterotrophic bacterial growth (19 mg C m(-2) d(-1))
Recent years have seen increasing interest in indirect genetic effects, i.e. influences on the phenotype that depend on the genotype of other conspecific individuals; however, the empirical evidence for such effects is still limited, especially in wild plant species. The present study of the clonal herb Sedum album assessed direct and indirect genetic effects on performance-related traits in a 4-y
What determines the seasonal and interannual variation of growth rates in trees in a tropical forest? We explore this question with a novel four-year high-temporal-resolution data set of carbon allocation from two forest plots in the Bolivian Amazon. The forests show strong seasonal variation in tree wood growth rates, which are largely explained by shifts in carbon allocation, and not by shifts i
Bryophytes have until now been absent from all hypotheses regarding the origin of insect pollination of seed plants. The discovery that both springtails and mites are able to transfer sperm in mosses makes it possible to suggest a ’Bryophyte precursor hypothesis of plant pollination’ stating that animal-mediated fertilization in mosses and insect pollination in seed plants is historically linked b
Terrestrial ecosystem models (TEMs) contain the coupling of many biogeochemical processes with a large number of parameters involved. In many cases those parameters are highly uncertain. In order to reduce those uncertainties, parameter estimation methods can be applied, which allow the model to be constrained against observations. We compare the performance and results of two such parameter estim
